Energy Efficiency

There are two types of technology change: Incremental and Disruptive. As a designer, disruptive is way more fun.

Incremental: How do we get more with less? For showers, building codes limit their consumption to 2.5 gallons per minute (gpm) while green building rating systems are pushing manufacturers to get more with less; down to 1.5 gpm. The problem is that at a certain point there is a physical limit to the incremental change and efficiency gains will level off. My gut says that for shower heads this point is somewhere around 1.2 gpm. Any 50% reduction is something to be proud of, but it has taken a long time.

Disruptive: What if we ask a different question altogether: “Is there a better way to take a shower?” A couple startups are trying to answer this question with what they call a cloud shower. Previously only available as a luxury shower add-on, the technology is similar to a type of commercial humidifier. They claim that their technology not only uses 75% less water, but also provides a much more luxurious showering experience: providing more even coverage and rinsing more effectively. We now have a sudden 75% drop in water consumption, which also results in a major drop in the amount of water that needs to be heated, which in turn saves a lot of money. All this by simply swapping out a shower head! Brilliant!

We hear a lot about industry leading net-zero energy and net-zero water schools happening in progressive communities around the globe, but we don’t hear as much about what’s happening with green schools here in the Mid-Atlantic. Local professionals will provide an update on net-zero energy and net-zero water schools in Virginia and Maryland. The interactive presentation will include a discussion of regional green school efforts and what challenges, and opportunities, lie ahead in the future.

This luncheon will be held at City Space, 100 5th St. NE, on the Downtown Mall, Charlottesville, VA. Doors open at 11:45 and the Seminar begins at 12:00. Luncheons are open to the public. Lunch is provided, attendance is free for GVGBC members and $10 for non members. Register Here

If you have been thinking about adding solar panels to power your home but have been priced out, that may all change soon. This startup called Rayton is claiming to have built a solar panel with 25% greater efficiency and 60% less expense. If they succeed, it is a game changer for alternative energy!

Thursday11/13 & Friday 11/14 UVA Sustainability Days
Events start at 9:30 amThursday and end by 2pm Friday. See schedule for exact times and locations
Take part in UVA Sustainability Days to celebrate and innovate sustainable solutions on Grounds. There will be sustainability-themed events such as a Poster Competition, Film Screening, Zero Waste Workshop, Panel Discussion, Hoos Talking Green, and much more! Please RSVP, as space is limited for some of the events. Free. Info. and RSVP at http://www.virginia.edu/sustainability/u-va-sustainability-days/

If you’ve been thinking about making your home more energy efficient but don’t know where to start, the Home Energy Checkup from LEAP is a really good and inexpensive way to have a professional check out your home and give you great advice. We just did our house and I had a lot of fun. Our coach was a wealth of knowledge and really friendly; he even insulated some of the pipes in our house free of charge. Overall it was a great experience and helped prioritize projects that will have the greatest effect for the least amount of money. Highly recommended.

The first thing you need to do before building any sort of solar-powered project is to figure out how much sun the site receives. Trees, mountains and houses can all block solar energy from reaching whatever you have collecting it. In the olden days you would go out to the site armed with a compass, protractor, cardboard, string and a washer and plot out the obstructions on paper. Now we have some slick apps for android phones and tablets to help us. Here’s a guide for making a Solar Site Survey Chart using apps for android with a little post processing on a computer.

1. Use the Solar Shading app to make a new project and trace the solid horizon. Follow the directions for the app; there is no need to repeat them here. Make sure that the program knows your position or things will be thrown off. It is important to trace just the mountains and other solid things that aren’t going anywhere because you certainly can’t change those. Use the share icon in the app to export the pdf of the report; it is useful as it is, but we’ll do more with it later.

2. Use the Solar Shading app to make another new project and trace the “green” horizon. This time, trace the outer edge of all the trees and any other objects that aren’t completely solid. Use the share icon in the app to export the pdf of the report; again, it is useful as it is, but we’ll do more with it later.

5. Use Photoshop, GIMP, or another image editor that allows the use of layers to superimpose and line up the solar chart made in step 4 over the chart that the app made in step 1. On a new layer use the paintbrush and masks to make a clean horizon on the chart. Hide the chart from step 1.

6. Now bring the solar chart that the app made in step 2 under the chart built-in step 6 just like you did in step 5. On a new layer use the paintbrush and masks to make a clean “green” horizon on the chart. Hide the chart from step 2. Put some text to let everyone know where in the world the survey was taken and you’re done.

7. Doing the survey with the less expensive augmented reality apps SunPlan and Sun Surveyor is a similar process, but is more labor intensive. Use the app to take augmented reality screenshots to create a panorama on a computer later. I like to turn on the winter and summer solstice sun paths in the app because it gives a nice reference point when using them later. It’s a good idea to take a panorama even if you used the Solar Shading app to make the solar chart because it shows what the obstructions are. They are the most valuable together.

8. Turn the images into a panorama using a panorama maker program like Microsoft ICE. The augmented reality pieces confuse these programs pretty badly, so it’s not going to be flawless. Let me know if you find a way to get a cleaner panorama!

10. Open Photoshop, GIMP, or another image editor that allows the use of layers to open the chart made in step 9 side by side to the panorama made in step 8. On a new layer use the paintbrush and masks to make a clean horizon on the chart from step 9 using the panorama as a reference. On a new layer use the paintbrush and masks to make a clean “green” horizon on the same chart using the panorama as a reference. Put some text to let everyone know where in the world the survey was taken and you’re done.

The first thing you need to do before building any sort of solar-powered project is to figure out how much sun the site receives. Trees, mountains and houses can all block solar energy from reaching whatever you have collecting it. In the olden days you would go out to the site armed with a compass, protractor, cardboard, string and a washer and plot out the obstructions on paper. I’ll let Builditsolar.com describe how to do that in detail: http://www.builditsolar.com/SiteSurvey/site_survey.htm

Here’s what an old-fashioned solar survey looks like:

Thanks to google sky map, everyone now knows that smartphones and tablets have all the sensors that one would need to make one of these charts digitally, plus a camera. The burning question is which app works the best and how do you make a chart with this technology? We pitted a few against each other using the same android smart phone hardware and here are the results. There is also a guide for creating this chart using some of the apps mentioned below.

1. Solar Shading: For the purpose of making a site solar survey chart, Solar Shading is by far the most capable app for android, which makes sense because it is the only one specifically designed to make this chart. The interface is a bit harder to get used to than the other apps, but it is by far the most powerful. You trace the obstructions to the sun either using the crosshairs with the camera or looking down the edge of the phone/tablet. Once you’ve completed tracing the horizon for a complete circle, the app generates the solar chart as well as two graphs showing the solar power generated and the penalty that the obstructions are causing during each month of the year. This app is easily the fastest way to accomplish the task and provides great looking reports, so it can be done at several locations on a site to find the optimal location on a site for a solar collector or a passive solar house. The only downside is the $16 price tag.

2. Sun Surveyor: This is an “augmented reality” application that displays sun paths and/or moon paths on the camera preview. This is the smoothest, most polished, and most feature rich of this type of app that was tested. The 3D compass, compass calibrator, and map view are nice additions to your smartphone toolkit. The augmented reality view shows any sun or moon path that you would like to display, as well as degree grid lines, which are very helpful in building a solar chart back at a computer using the images captured with this application. These images can then be taken back to a computer and obstructions plotted onto a chart if needed. This is a nice companion to the Solar Shading app to have pictures for later reference that are geographically referenced. This app carries a $6.49 price tag.

4. Helioserver:Works similar to the solar shading app, but the interface is confusing and not very polished. It probably does a lot of heavy lifting in the background, but only gives you an output of what direction to point solar panels; I wasn’t able to accurately come up with reference points from the output to plot the data onto a chart. I couldn’t figure it out, not to say it can’t be done.If it works for you, the $1.33 price tag is certainly the cheapest.

Conclusion: After actually doing a few surveys with all of the software, I personally choose to use the Solar Shading app to do the heavy lifting. Its professional looking output can be imported directly into Photoshop and excel. It collects real data in a couple of minutes so that several locations can be investigated to find the optimal solar site location in a short amount of time. I also use Sun Surveyor and SunPlan to get a good panorama of the site for reference further down in design. They are both very similar, so use Google Play’s 15 minute refund policy to try them both out before you decide which one you prefer.

The more research you do into renewable resources, the more you realize that matching demand for power to the renewable supply is the trickiest part. According to this study, for people that are away at work in the middle of the day, it makes more sense to point solar panels south-west instead of directly south. Makes sense right? Well, yes and no. If you aren’t attached to the grid, or your power company doesn’t allow net-metering and you work all day then yes, this makes perfect sense, why not make the power when you’re using it. If you have net-metering from your power company, why not produce the most power and use the grid as your battery; then due south is still the way to go.